In terms of consultancy services, Professor Lau serves as a consultant of the WHO Informal Expert Group on Community Engagement Research during the COVID Pandemic, the WPRO Informal Network on Hepatitis Stigma & Discrimination, WHO guideline groups on HIV self-testing and Partner Notification, Disease & Health Management Committee of National Chinese Hospital Association, and as a senior consultant of the Centre for Disease Control and Prevention of the Hunan and Jiangsu Provinces and the Institute of Family Planning and Research in Shenzhen. He provided professional consultancy to international organizations such as the Family Health International, HLSP and the Cambodian government. Professor Lau is also very active in community services. He has been involved in various advisory governmental committees such as those in HIV/AIDS, rehabilitation, civic education and youth development etc. He chaired the Hong Kong Coalition for AIDS Services Organizations from 2000 to 2002 and has been a Director of AIDS Concern in Hong Kong since 2005 to present and an advisor of the Community Health Organization for Intervention, Care and Empowerment (CHOICE).